One way of ventilating a building is by leveraging the power of “stack effect”. To understand how it works, consider the temperature difference of air inside and outside a building. Warm air inside a building tends to rise and seek an exit. Since nature abhors a vacuum, cooler air from outside flows in to occupy the space left by the warm air. This cycle repeats countless times every day in a process called stack ventilation so long as vertical pressure differences exist. Take note that this phenomenon may occur naturally or by design.
Although stack ventilation allows air to circulate in a building, it may not contribute to sufficient airflow. This is because a building must have large openings to allow such flow to occur freely. Secondly, this type of ventilation may actually cause the temperature in some rooms in a building to be higher. For example, in a building with several floors, the rising warm air will make rooms in upper floors hotter. Professionals in the construction industry call this effect stratification.
Nevertheless, this type of ventilation can take place even when there is no wind pressure. One can also use this type of ventilation in a building where wind-driven cross ventilation is impossible to achieve. Take note that stack ventilation can only take place when the air temperature inside the stack is higher than the air outside.
The beauty of relying on natural ventilation is you do not have to incur extra costs to keep your home cool. Remember most mechanical ventilators consume electricity in order to circulate air throughout a building. Secondly, you do not have to worry about maintenance costs. Thirdly, natural ventilation does not pollute the environment by releasing harmful gases such as carbon monoxide or carbon dioxide.
Unlike other forms of ventilating a building, stack ventilation is natural. This method depends on hot air rising in an enclosed space allowing cold air to replace it.